Currently, it is known that, following the implant of a prosthesis inside the human body, a post-operation infection can arise: the prosthesis can in fact be reached by bacteria present in the implant site or in the surgical environment, which colonize the surface thereof, involving the unsticking of the prosthesis from the bone or articular site.
In these cases, the steps to be followed for defeating such infection provide for the removal of the infected prosthesis from the implant site, the implanting of an antibiotic spacer, or a spacer capable of releasing antibiotic and, finally, when the infection has been totally defeated, the installation of a new prosthesis.
The use of spacer devices is necessary in order to maintain substantially unaltered the shape of the bone site or articular site in which the new prosthesis will be implanted, as well as in order to defeat the infection underway due to the release of antibiotics.
This procedure is the re-prosthetization procedure known as “two stages” or “at two times”, because the healing from the infection and the implant of a new prosthesis require two implant/treatment steps.
The use of a spacer during the “two stages” or “at two times” procedure involves the presence of several bone requirements, such as the need to have an articulation in which the ligaments are substantially integral, in a manner such that the spacer is stable once implanted, and in which the corresponding bone part has not been excessively resected, in a manner such that after the step of implant and removal of the spacer device, it is possible to fix the new prosthesis in a correct and stable position.
There is also a “one stage” surgical procedure that provides, in a single operation action, the removal of the infected prosthesis and its substitution at only one time with a new prosthesis. Nevertheless, such technique assumes the previous identification of the pathogen, in order to be able to employ, for the prosthetic re-implant, cement admixed with the specific antibiotic aimed to defeat the identified pathogen.
Such “one stage” procedure is quicker and, for this reason, involves less physical and mental stress in the patient, but it is indicated for the infections with low virulence, since it is seen that the onset of a new infection has been encountered in a—albeit small—percentage of cases. Such re-infection is instead less common in the case of the “two stages” surgical procedure.
There is therefore the need, for the surgeon, to have a prosthetic device, both first-implant and revision, provided with antibacterial power or comprising pharmaceutical or medical substances in general, such to prevent the onset of infections and/or to heal those present, and such to prevent an operation of re-prosthetization of “one stage” or “two stages” type.